Spinal dysraphisms are the spectrum of disorders where the child’s spine and spinal cord do not form properly during pregnancy.
- 1-3/100 live births
- Spinal Bifida: neural tube closing defect where there is incomplete closing of the membrane around the spinal cord
Types of spinal dysraphisms
| Open Spinal Dysraphism | Closed Spinal Dysraphism |
|---|---|
| Spinal Bifida Aperta | Spinal bifida occulta |
| 1. Meningocele | 1. Dorsal dermal sinus |
| 2. Myelomeningocele | 2. Lipomyelomeningocele |
| 3. Open myelomeningocele | 3. Diasteomatomyelia |
| 4. Neurenteric cyst | |
| 5. Thickened filum terminale | |
| Combination of genetic and environmental factors | No/ mild clinical features Hairy patch, dimple, café au lait spots, swelling |
Risk factors of Spinal dysraphisms
- Previous pregnancy (4%)
- Folic acid deficiency
- Obesity
- Maternal diabetics
- Anti-epileptic medication
Diagnosis of Spinal dysraphisms
- USG
- Amniocentesis @ 15-18 weeks
- AFP ↑
Management Options for Spinal dysraphisms
Folic acid supplementation in 1st trimester of pregnancy and before pregnancy (400 ug)
Open Spinal dysraphisms
Surgically closure is done before and after birth.
Clinical Features:
Early diagnosis:
- Myelomeningocele and meningoceles are usually obvious at birth in the shape of a saccular lesion overlying the lumbar spine
- Covered only with the membrane or with membrane and skin
- In open myelocele : neural elements from the floor of the cyst and CSF leak continuously from the open cord
- Baby’s posture: Suggest paralysis
- Deformities
Due to combination of factors such as muscle imbalance, lack of movements and abnormal limb position
- Equinovarus (calcaneovalgus of feet)
- Recurvatum deformity at the knee
- Hip dislocation (in utero)
- Neurological evaluation after birth is necessary
Spinal bifida occulta
Encountered accidentally as an incidental finding on abdominal x-ray
May signify seriously if
- Dimple
- Tuft of hair
- Pit
- Pigmented lesion
There may be associated abnormalities as
- Tethering of conus medullaris
- Splitting (diastematomyelia)
- Cyst, lipoma of cauda equine that might be needed to be identified
In Children with Spinal Bifida
Spina bifida will develop the following symptoms:
Mild neurological symptoms (enuresis, urinary frequency or intermittent incontinence)
Neurological examination may reveal weakness and some loss of sensibility in lower limb.
Hydrocephalous may be present
In Older children with Spinal Bifida
Physical signs (child) above mentioned + develops :
- Clawing of toes
- Change in gait pattern
- Incontinences
- Abnormal sensation
The delayed presentation will be attributed to ‘tethered cord syndrome’.
Tethering may be secondary to early surgery reconstruction to a major defect or to conditions such as diastematomyelia and with growth, there is progressive damage to the cord and/or nerve roots
MRI + gadolinium enhancement is the investigation of choice
Neurosurgical release before any further neurological damage occurs should be done
Treatments options for Spinal Bifida
Recently, intrauterine surgery (open or fetoscopic) has been attempted
Closure of defect is possible but a reduction of neurological disability has not yet been identified
After birth, care must be taken to address the wound and prevent infection of these vulnerable tissues
Neurological closure of the defect should take place within 48 hr of birth in order to prevent drying/ ulceration/ infections
After the back heals (wks), the degree of hydrocephalous is accessed
Almost all children have Arnold-Chiari malformation with the displacement of the posterior fossa structure through the foramen magnum.
90% of patients require treatment with VP Shunt ( due to ↓ risk of further damage to CNS)
Clinically ↑ ICPs will lead to learning difficulties and other problems
If a child’s neurological status changes unexpectedly shunt problems such as infection, or blockage should be considered.
VP drainage can be maintained ( If necessary, by changing the valve as the baby grows) for 5 – 6 years and by which time the tendency to hydrocephalous usually ceases.
Orthopedics Operations:
- The late functional outcome can’t be predicted (except in mild cases)
- Most patients with myelomeningocele will never be functionally independent
- Maintainance and development of intellectual skills and upper limb function are often more important
- Physiotherapist:- working to correct, or indeed prevent, joint deformity, risk of fracture, and orthotics must take into consideration
- Latex allergy is present in some children, so should be considered.
Regional Surgeries for Spinal Bifida
SPINE:
- Scoliosis / Kyphosis are most common in children due to a combination of muscle weakness and imbalance
- Associated other congenital anomalies
- Tethered cord syndrome
- Distal tethering is almost inevitable after the repair of myelomeningocele and this may be harmless, but it can cause pain and progression of neurological dysfunction during the phase of rapid growth (in some cases it gives rise to scoliosis)
- Indications of Operative release:
- Increasing pain and neurological dysfunction
- Progressive spinal deformity
- Kyphosis:
- Results in stretching and breakdown, or chronic ulceration, of the overlying skin posteriorly and compression of abnormal and thoracic viscera anteriorly
- Treatment is difficult and may require localized (vertebral resection and arthrodesis)
- Neuromuscular scoliosis:
- A long C-shaped curve which is usually progressive and makes sitting particularly difficult is unlikely to respond to a brace
- Molded seat inerts for a wheelchair are essential to aid sitting balance and may help to reduce curve determinations
- Surgery is generally required
Hip Surgery
- Aim to secure hip to have enough movements
- To enable children both stand up in
- Knee-ankle-foot orthosis (KAFOs)
- Reciprocating gait orthosis (RGOs)
A. If neurological problem above L1 then all muscle groups are flaccid and splinting is only option
B. With lesion below S1, hip flexion contracture is a most likely a problem that is corrected by elongation of psoas tendon combined with the detachment of both heads of rectus femoris from the ilium
C. In between lesions, muscle imbalance is the main problem and many hips will be subluxated or dislocated by early childhood but lack of evidence of improvement by open hip relocation
Knee Surgery
- The aim is straight knee suitable for wearing orthosis and using gait through training devices
- In older children, FFD may present
- If physiotherapy and/or use of orthosis fails to correct deformity then Hamstring lengthening and posterior capsular release is done
- For some child born with hyperextension contracture, physiotherapy, serial casting, V-Y quadricepsplasty and hamstring lengthening/ relocation is usually done
- After surgery, Orthotic devices are required for Standing/ Walking.
Foot Surgery
- A most common problem in children with spinal Bifida
- Aim: mobile foot with healthy skin and soft tissue
- Flail foot: ANKLE Foot Orthosis
- Talipes equinovarus deformity is more severe and resistant to treatment than idiopathic clubfoot
- Ponsetti + Percutaneous tenotomy
- The relapse rate is high so required surgical treatment
- Vertical talus: reverse posetti and surgical correction
- Toe deformities: High toe box, orthopedics shoes.
Diastematomyelia
- Type of split cord malformations
- Bony spurs form and longitudinal split in the spinal cord
- In diplomyelia:- cord is duplicated rather than split
- The patient presents as a tethered cord
- Patient with leg weakness, LBPs, scoliosis, and/or incontinence
- If progressive neurological signs present:- resection of bony spurs, otherwise observation
Tethered cord syndrome
- Defined as “progressive neurological deficit from the restriction of the spinal cord movement and traction due to physiological or anatomical factors”.
- Present with gait disturbances, feet disturbances, bladder disturbances, vague leg pain + neurological deficit
- MRI shows conus to be at a lower level than L2-L3 disc space
- Can be due to thickened Filum terminale (>2 mm) or
- Lipoma
- Lipomyelomeningocele
- Other dysraphic conditions
- Treatment: Surgery if symptoms are developing
